Definitions

1. adjective

relating to or resembling a crown, especially in being rounded or curved at the top

“The coronal structure of the mountain peak was breathtaking.”

2. noun

a crown-like structure, especially one forming the upper part of a solar prominence or a prominence on the surface of the Sun

“A coronal mass ejection occurred on the surface of the Sun.”

3. noun

the upper part of a cell, especially the part of the cell membrane that forms the outer layer of a cell

“The coronal region of the cell was found to be highly reactive.”